Florida Sen. Marco Rubio is looking to reestablish his claim as the mainstream Republican who can unite the party. And he can't get more mainstream than the latest Georgia endorsement he landed.

Alec Poitevint said Thursday he was backing the candidate, who is trying to recover his footing after a fifth-place finish in New Hampshire.

Poitevint chaired Sonny Perdue's 2002 campaign for governor and David Perdue's 2014 Senate bid. He was also an ex-chairman of the Georgia GOP and was tapped to organize the 2012 Republican National Convention in Tampa. He has been called the "ultimate insider in Georgia's Republican Party."

"Having endured almost eight years of President Obama, Americans are frustrated with the direction of our country. I am one of them. The only way to turn it around and advance our conservative cause is to win in November," said Poitevint. "I believe the only candidate who can do that is Marco Rubio. His conservative values are second to none.”

Rubio has racked up a string of endorsements in Georgia in the runup to the March 1 primary, including Rep. Lynn Westmoreland last week and a gaggle of state lawmakers a few days ago.

Poitevint's endorsement underscores a divide among those circling the Perdue family orbit. Sonny Perdue and his former top aide, Eric Tanenblatt, both back former Florida Gov. Jeb Bush. John Watson, another former top aide to the governor, supports Ohioan John Kasich.